Sift together powdered sugar and almond flour twice for smoothness; set aside.

Beat egg whites in a clean bowl until foamy; add cream of tartar, then granulated sugar until stiff peaks form.

Fold in green gel food coloring carefully until uniform.

Gently fold sifted almond flour mixture into colored egg whites until a smooth batter forms.

Pipe tree shapes or rounds on lined baking sheets; tap to release air bubbles.

Let macarons rest until they form a skin, about 30-60 minutes.

Bake at 300°F for 14-16 minutes; allow to cool completely.

Beat softened butter until fluffy; mix in powdered sugar, vanilla, heavy cream, and salt until creamy, then fold in crumbled snack cakes.

Assemble by pairing macaron shells with filling and creating a sandwich.

Melt white chocolate and drizzle over assembled macarons; add sprinkles for decoration.

Refrigerate in an airtight container for at least 24 hours before serving.